1. Field
Embodiments relate to a lamp heater and a drying apparatus including the same.
2. Description of the Related Art
Secondary batteries, e.g., lithium (Li) secondary batteries, are widely used in portable electronic/electric devices, e.g., cellular phones, laptop computers, camcorders, etc., because their operation voltage may be about three times higher, and their energy density per unit weight may be higher, compared to Ni—Cd and Ni-MH secondary batteries.
The secondary battery may include an electrode assembly, a can containing an electrolyte solution such that lithium ions can migrate between electrodes of the electrode assembly, and a cap assembly sealing the can. The electrode assembly may include a positive electrode plate having a positive electrode collector covered with a positive electrode active material and a positive electrode tab electrically connected to a side of the positive electrode collector. The electrode assembly may also include a negative electrode plate having a negative electrode collector covered with a negative electrode active material and a negative electrode tab electrically connected to one side of the negative electrode collector. The electrode assembly may also include a separator between the positive and negative electrode plates.
The positive and negative electrode plates of the electrode assembly may be formed by applying slurries including respective electrode active materials to the electrode collectors made of, e.g., a metal foil or metal mesh. The slurry may be prepared by mixing a solvent, a plasticizer, electrode active material, and a binder. In order for the electrode active material to be stably adhered to the electrode collector, a drying process for removing the solvent may be performed after the slurry is applied to a surface of the electrode collector.
The drying process may include a process of supplying heated air to a surface of the slurry as well as a process of heating the slurry using a lamp heater. In the process of supplying the heated air, a drying speed may vary depending on a position of the slurry relative to a flow direction of the heated air. Thermal energy of the heated air may be discharged along with the evaporated solvent, so that energy efficiency of the drying process may be low. The process of heating the slurry using the lamp heater may exhibit relatively higher drying efficiency and shorter drying time.
In the drying process using the lamp heater, power of the lamp heater may be regulated using a power regulating means, e.g., a thyristor power regulator (TPR). In the drying process using the lamp heater, a wavelength output from a lamp may be selected according to characteristics of a material to be dried. A peak wavelength output by the lamp heater may vary depending on applied power in view of characteristics of the lamp heater. However, in the case of a three-phase power source lamp capable of easily supplying high-capacity power, a phase balance may not be kept unless the lamp is switched on by a multiple of three, and thus drying efficiency and heat transfer efficiency may be lowered.